Daytime Wounds Heal More Quickly Than Those Suffered At Night

Biologists and neuroscientists long thought the body’s time keeper, our circadian clock, resided only in the brain. In mammals, that place is a region of the hypothalamus called the suprachiasmatic nucleus, which receives signals from the eyes. However, recent research demonstrated that cells in other parts of the body—including the lungs and liver—keep their own time. Researchers aren’t quite sure how they maintain their own 24-hour schedule, whereas other cells need external reminders.

The researchers then showed in mice that skin wounds suffered during their waking hours healed better than ones incurred during their resting hours. What’s more, those increases lined up with the cell culture data. About twice as many fibroblasts migrated into the daytime wounds as nighttime ones. “We were really astonished,” O’Neill says.

Finally, O’Neill and colleagues looked for evidence of such an effect in humans. The team examined data from the International Burn Injury Database, which records, among other things, the time of day an injury occurred. The analysis revealed that nighttime burns took an average of 11 days longer to heal than burns incurred during the day, the researchers report today in Science Translational Medicine. O’Neill emphasizes the need for further controlled clinical studies to confirm the effect. He speculates that if real, the effect could help people recover more quickly by scheduling surgeries in time with their personal circadian rhythms, earlier for morning larks and later for night owls.

Read the article in its entirety on sciencemag.org:
http://www.sciencemag.org/news/2017/11/daytime-wounds-heal-more-quickly-those-suffered-night?utm_campaign=news_daily_2017-11-08&et_rid=336989572&et_cid=1652286